lewis played sergeant nicholas brody, america's newest war hero freed after eight years of captivity in iraq >> brody is really a victim of war. that's what he is. he comes back absolutely eviscerated by war. damaged irreppably. and that's the human cost of war. >> reporter: carrie suffers from a by polar disorder, a cassandra character who speaks the truth that no one else believes. >> you don't know what you're doing. >> reporter: by the end of season one, she unravels and undergoes electro shock therapy. while brody at the last minute aborts his suicide bomb plot. >> got a call for you from your daughter. >> this thing just came right out of the gates. it was, you know, within episode 2 or 3 people were talking about it. >> reporter: but lewis never imagined who was talking about the show. last spring he was invited to a state dinner at the white house for the british prime minister. president obama told him he was a fan of homeland. >> you know, i said to him and david cameron halfway through dinner, when do you guys get to watch tv because aren't you supposed to be running the free worl